Multiunit vacuum tube



Dace 112 195@ J. J. MULLER 2,533,2

MULTIUNIT VACUUM TUBE Filed July 31, 1947 2 Sheets-Sheet l INVENTOR JEAN \J- MUL L 5/? ATToN EY em 12, 1950 J. J. MULLER 2,533,280

MULTIUNIT VACUUM TUBE Filed. July 51, 1947 2 Sheets-Sheet 2 INVENTOR L/E /Y u. MULLER ATTO RN Patented Dec. 12, 1950 UNITED MULTIUNIT VACUUM TUBE Jean Jacques Muller, Paris, France, assignor to International Standard Electric Corporation, New York, N. Y., a corporation of Delaware Application July 31, 1947, Serial No. 765,163 In France March 16, 1943 Section 1, Public Law 690, August 8, 1946 Patent expires March 16, 1963 1 Claim.

The present invention relates to an improvement in vacuum tubes for certain devices employed in the art of radio waves, particularly socalled inverted amplifiers in which the grid is grounded.

These amplifiers employ triode tubes, and the characteristic feature of the mounting consists in grounding the grid: the energisation is effected by varying the potential of the cathode. When two triodes are push-pull connected in such an arrangement, both grids are grounded.

One of the objects of the present invention is the replacement, particularly in inverted amplifiers, of the two tubes mounted in pushpull by a single tube having the same elements as the two tubes.

According to one of the features of the present invention, the tube groups together in the same envelope the constituent elements of two triode tubes, these elements being disposed on both sides of a central metallic wall located within the envelope. This metallic wall. whether continuous or not, acts as a screen or partition between the two triodes and also serves as a connection for the grids. The word partition may be taken to designate this element, because the terms screen and plate are already currently employed in the art of vacuum tubes to designate diiierent constituent elements.

Embodiments of the invention will be described with reference to the accompanying drawings, in which:

Figs. 1 and 2 are schematics of the principle of the tube. Fig. 1 illustrates indirect heating of the cathodes.

Figs. 3 and 4 illustrate embodiments of the invention, taken as examples.

Figs. 5, 6 and 7 show examples of the construction of the partition grid details.

In these figures, like elements are indicated by the same reference numbers.

In the embodiments shown by way of example, the tube consists of a glass bulb I containing the same elements as a triode, i. e. cathodes 2, grids 6 and anodes 3. The cathodes and anodes are secured by any known method.

The partition together with the grids forms an assembly that is secured in any known manner.

Contact pins 2, 3. 5, 2|, 22. 23, 24 permit the connecting of the various inner elements of the tube to the outer circuits.

Figs. 3 and 4 show the respective positions of the various parts located on one side of the partition. To make the drawing more understandable, the anode is broken away.

Fig. 3 illustrates the case in which the grid is secured laterally to the partition. This arrangement is easy to make, and the grid is firmly held against the partition.

This arrangement may be modified in various ways. One possible solution consists in connecting the grids at the end, as shown in Fig. 4.

Fig, 4 shows an embodiment of the grid-partition assembly. The grids consist of a wire wound helically on 4 pins (not shown) soldered to the partition and perpendicular to the same.

Figs. 5 and 6 have to be examined together, Fig. 6 being a plan view of the equipment constructed according to Fig. 5. A plate has its edges provided with saw cuts. A wire is then wound by passing it around these kerfs. In Fig. 5, the winding is made as a circular spiral. However, the spiral may be formed on a cylinder having a difierent base, but as well adapted as possible.

Figs. '7 and 8 show a difierent style of mounting. The grids, which consist of wires, are soldered to the plate or are held in position by a rod 40 soldered to the plate.

Figs. 9 and 10 show an assembly formed solely of the same wire wound helically on a suitably positioned set of pins. The partition is formed by the flat loops.

It is evident that the various examples are descriptive, but not limitative.

It is evident that the application of the present invention is not limited to inverted amplifiers. It may be employed in all cases in which it can replace two triode tubes that have their grids joined by a short connection and have as low an impedance as possible.

Although the present invention has been described for certain examples of embodiment, it is evident that it is by no means limited thereto, and that the same are capable of numerous variants and modifications without departing from the scope of the invention.

Having now particularly described and ascertained the nature of my said invention and in what manner the same is to be performed, I grids and the partition are at equipotential and declare that what I claim is: the partition also electrically shields the cham- An electron discharge device which comprises IS a v o each ot er. a gas-tight envelope, a metallic partition within JEAN JACQUES MULLER. and attached to said envelope which subdivides 5 the envelope interior into a plurality of cham- REFERENCES CITED hers a plurality of anodes and a plurality of The following references are of record in the cathodes, one of each being supported within fil f this patent; each of said chambers, a plurality of grid ele- V k ments, one being in each chamber disposedbe- 10 UNITED STATES PATENTS tween the anode and the cathode therein, said Number e Date grid elements being constituted of a single wire 2,044,369 Samuel June 16, 1936 helix wound around and being both mechanically 2,163,247 Samuel June 20, 1939 and electrically connected to said partition 2244:261 Rath June 3, 1941 whereby, during operation of the device, the 15. 

